5 fast i2c & smbus, Fast i2c & smbus, Come-msp1 / features and interfaces – Kontron COMe-mSP1 User Manual

Page 31

COMe-mSP1 / Features and Interfaces

4.5

Fast I2C & SMBus

The COMe-mSP1 integrates two configurable I2C buses. The external I2C provided via US15W GPIOs on COM Express®
Connector Pin B33/B34, the LVDS I2C from US15W SCH is available on COM express® connector pin A83/A84. The I2C
interface offers full MultiMaster and Clock Stretching support. Fast I2C and SMBus clock speed depends on the CPU
performance and differs between ATOM™ Z510 and ATOM™ Z530 modules. See the tables below for measured values on
COMe-mSP1 with BIOS NOW1R118.

JIDA/external I2C speed

JILI I2C speed

SMBus speed

Setup

ATOM™ Z510

ATOM™ Z530

ATOM™ Z510

ATOM™ Z530

ATOM™ Z510

ATOM™ Z530

Extra high

not supported

375 kHz

418 kHz

Very high

166 kHz

215 kHz

80 kHz

125 kHz

214 kHz

270 kHz

High

80 kHz

110 kHz

55 kHz

80 kHz

57 kHz

86 kHz

Medium

41 kHz

60 kHz

34 kHz

50 kHz

35 kHz

46 kHz

Slow

10 kHz

15 kHz

9.6 kHz

15 kHz

7.4 kHz

10 kHz

Very slow

1 kHz

2 kHz

1.5 kHz

2 kHz

0.7 kHz

1 kHz

Ultra slow

0.7 kHz

1 kHz

not supported